| B27 | Infectious mononucleosis | NON-BILLABLE CODE |
| B27.0 | Gammaherpesviral mononucleosis | NON-BILLABLE CODE |
| B27.01 | Gammaherpesviral mononucleosis with polyneuropathy | BILLABLE CODE |
| B27.02 | Gammaherpesviral mononucleosis with meningitis | BILLABLE CODE |
| B27.09 | Gammaherpesviral mononucleosis with other complications | BILLABLE CODE |
| B27.1 | Cytomegaloviral mononucleosis | NON-BILLABLE CODE |
| B27.10 | Cytomegaloviral mononucleosis without complications | BILLABLE CODE |
| B27.11 | Cytomegaloviral mononucleosis with polyneuropathy | BILLABLE CODE |
| B27.12 | Cytomegaloviral mononucleosis with meningitis | BILLABLE CODE |
| B27.19 | Cytomegaloviral mononucleosis with other complication | BILLABLE CODE |
| B27.8 | Other infectious mononucleosis | NON-BILLABLE CODE |
| B27.80 | Other infectious mononucleosis without complication | BILLABLE CODE |
| B27.81 | Other infectious mononucleosis with polyneuropathy | BILLABLE CODE |
| B27.82 | Other infectious mononucleosis with meningitis | BILLABLE CODE |
| B27.89 | Other infectious mononucleosis with other complication | BILLABLE CODE |
| B27.9 | Infectious mononucleosis, unspecified | NON-BILLABLE CODE |
| B27.90 | Infectious mononucleosis, unspecified without complication | BILLABLE CODE |
| B27.91 | Infectious mononucleosis, unspecified with polyneuropathy | BILLABLE CODE |
| B27.92 | Infectious mononucleosis, unspecified with meningitis | BILLABLE CODE |
| B27.99 | Infectious mononucleosis, unspecified with other complication | BILLABLE CODE |
